The arrangement of the LED and the LED light source specification determines the basic drive. led desk light driver function is limited in a certain range of operating conditions, flows through the LED current, regardless of how the input and output voltage changes. The most common is the use of the transformer to be electrically isolated. LED lighting design factors to be considered are discussed.

An LED drive General requirements

Drive the LED is facing a lot of challenges, such as the forward voltage changes with temperature, current changes, there will be differences in different individuals, different batches, different suppliers of LED forward voltage;, LED color Point "also with the change of the current and temperature drift.

In addition, applications often use multiple satellites LED This involves many LED arrangement. The various permutations way preferred single-string LED driver series, because in this way regardless of changes in forward voltage, output voltage (Vout) How to "drift" provides excellent current matching performance.

Of course, the user also can be used in parallel, series - parallel combination and cross-connect arrangement (Figure 1), for the need to match each other "LED forward voltage application, and get other advantages. Cross-connect, if one LED due to failure to open, only one dynamo flashlight drive current in the circuit will be doubled, so as to minimize the impact on the entire circuit.